When John Elway announced that Vance Joseph would return for the 2018 season, saying the Broncos believe in Joseph as a head coach, he added that together they would look to improve in all areas. Unspoken is the most obvious need for improvement. Since Elway wooed Peyton Manning for his career swan song abutting the Rocky Mountains, Elway has failed to deliver a viable successor at quarterback. The results have been predictable, as they are throughout the NFL when the player at that position is not a known asset. In the two seasons following Manning's retirement, Denver has gone 14-18, including a 5-11 mark in Joseph's first season on the job. Joseph was one of the fortunate ones -- Elway clearly recognized that he was hamstrung by a cast that includes Paxton Lynch, a first-round draft pick who has struggled to get on the field, and Trevor Siemian, a former seventh-rounder who has started 24 games.

The quarterback conundrum looms not only over the coaches who survived through the end of the season, but even more over the jobs that are now vacant:

CHICAGO BEARS: This is fascinating: On Monday, general manager Ryan Pace said the Bears were discussing allowing quarterback Mitchell Trubisky, who just finished his first pro season, to have a say in the head-coaching selection process. That would be unorthodox, to say the least. But whoever has a voice, finding someone who can develop Trubisky will be a priority for Pace, and having the ability to mold a franchise quarterback will be a powerful draw for an offensive coach, even if the power dynamic could be skewed by having Trubisky help pick his new boss. Could the Bears try to find the next young coordinator -- a Sean McVay of the Midway -- to team with Trubisky?

NEW YORK GIANTS: After the dramatic benching of Eli Manning and the subsequent reversal capped the unraveling of the season, new general manager Dave Gettleman has indicated he wants to go forward with Manning. But for how long? The Giants have the No. 2 overall pick in the 2018 NFL Draft, and the class is considered deep in quarterback talent. Big decisions await -- for Manning himself, who must decide if he wants to be a bridge quarterback, and for Gettleman, who must decide if he loves any of the draftable quarterbacks enough to pick one instead of filling other holes, and who must manage the end of Manning's career.

INDIANAPOLIS COLTS: The key question for every candidate to be the Colts' next head coach: What is the long-term prognosis for Andrew Luck's shoulder, and can I talk to the doctors? If the Colts are convinced it is sound, this is one of the most covetable jobs in the league, because a healthy Luck makes this team a contender, particularly because then the third overall draft pick could be used on another building-block piece. But the Colts were convinced Luck would play this season, too, and instead, he never saw a snap, so buyer beware. If there is any concern about Luck's viability, it will scare off candidates who would know they have to draft another quarterback and start over. Interesting to note: In the post-mortem press conference Monday, GM Chris Ballard insisted the team was not all about Luck, while owner Jim Irsay all but promised Luck would be back.

ARIZONA CARDINALS: Bruce Arians leaves behind a team at the start of a massive transition. Quarterback Carson Palmer (38 and coming off a season that ended in October due to a broken arm) announced his retirement on Tuesday, and receiver Larry Fitzgerald (34) could be done, too. Any candidate will want to know what the plan is to acquire a quarterback -- for instance, are the Cardinals willing to shell out the money required to potentially sign Kirk Cousins? Those coaching candidates will look around and see the young, dynamic quarterbacks in Los Angeles and San Francisco and know they have to get someone who can get the offense to stay with them.

DETROIT LIONS:Matthew Stafford is a powerful draw for candidates, and his comfort level with the offensive coaching staff -- he has lobbied for the Lions to keep coordinator Jim Bob Cooter -- could make for an easy transition for a defensive-minded head coach. Still, firing Jim Caldwell and his winning record (36-28 and two playoff appearances in four years) sets a high bar for success for whoever takes this job: It's win big or else.

OAKLAND RAIDERS:Derek Carr was hurt and regressed this season, and righting him will be the priority of the next coach (looking at you, Jon Gruden). There is a reason -- beyond copious amounts of money -- for this job to finally pull Gruden out of the broadcast booth and back to the sideline. Carr is an elite quarterback with enormous potential. Consider that if he hadn't gotten hurt late last season -- or this season -- Jack Del Rio might have a few playoff victories under his belt, along with, probably, his job.